Preptests 60 Answers and Explanations (By Ivy Global) Section 1 Logical Reasoning

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1 Section 1 Logical Reasoning 1) Analyzing the Stimulus Jim s conclusion that the sample contained iron is decisive. His evidence is certain: the magnet attracted the substance. This reasoning is implied and is formal: because magnets attract iron, any object which is attracted by magnets must contain iron. - We can test his reasoning by applying the Sufficient/Necessary analytical technique. o If a Magnet is Applied -> Iron is Attracted, all we can conclude is that If Iron is Not Attracted -> A Magnet has Not Been Applied. o Jim s reasoning is invalid. a) While this would certainly create a flaw in Jim s reasoning if it were true, it is a challenge to the evidence and not to Jim s reasoning. b) Even if this were true, it would not invalidate Jim s reasoning. c) Even if it were true that the incorrect orientation of the magnet meant that the substance was attracted to the magnet when it should not have been, it would not invalidate Jim s reasoning. d) This is the correct answer because it exposes the flaw in Jim s reasoning. If it is true that magnets attract other substances apart from iron, Jim s reasoning that any object which is attracted by magnets must contain iron would be invalid. e) Since the magnet attracted the substance, this is irrelevant. In any case, it still fails to challenge Jim s reasoning. The correct answer is the only one that demonstrates that Jim s reasoning is flawed. It shows that the whole argument is invalid. 2) Analyzing the Stimulus The conclusion that Horatio s book was misplaced or stolen is decisive. The evidence is certain: the book has not been checked out to a borrower, nor is awaiting shelving, nor is part of a special display. This reasoning is explicit and is formal: there are only five possible explanations for a missing book and since three have been eliminated, one of the remaining two must be true. - This argument rests on the assumption that there are only five possible explanations. If there were others, the conclusion would be incorrect. a) The reasoning does not apply use another object to draw general conclusions; the conclusion pertains to a specific object: Horatio s book. b) The reasoning does not point to a deficiency in a system. c) The reasoning does not contain a rebuttal. d) No generalization has been rejected.

2 e) This is the correct answer because it describes the reasoning in the argument. The reasoning is that since there are only five possible explanations for a missing book and since three have been eliminated, one of the remaining two must be true. In other words, the other possible explanations have been ruled out. The correct answer is the only one that describes the reasoning in the stimulus. 3) Analyzing the Stimulus This stimulus contains only background facts which cannot be questioned. Though the last sentence could have been interpreted as a conclusion, because we know that it is inference question, we know that the stimulus contains only facts and evidence and no conclusions. a) This could very well be true, but to make this conclusion, a number of assumptions (that are not contained in the stimulus) would have to be made. For example, improvements to technology could mean a reduction even if regulations are not followed. b) This is the correct answer because it draws a conclusion based on the facts in the stimulus. In fact, the answer only reiterates the fact contained in the last sentence. c) Again, this could very well be true, but to make this conclusion, a number of assumptions (that are not contained in the stimulus) would have to be made. In the future, these new regulations might be followed, for example. d) There is nothing in the stimulus to suggest this. e) While this may be true, this is a fact that is not contained in the stimulus. The correct answer is the only one that uses only the facts in the stimulus to draw a straightforward conclusion required by the question stem (a proper inference). In fact, this question seems to be too easy because the answer simply repeats information contained in the stimulus. 4) Analyzing the Stimulus The ecologist s conclusion that the prediction that a landfill availability crisis will occur is indecisive. The ecologist acknowledges that prediction rests on an unlikely assumption: in other words, there is a faint chance that there will be a crisis. The evidence is uncertain: again, the assumption that no new landfills will be opened is unlikely, but not impossible. This reasoning is explicit and is informal: because the prediction that a crisis will occur is based on an assumption that is unlikely, it is unsound. a) A case can be made for this answer, though sit is not a good one. However, it does not address how the claim relates to the Ecologist s argument. b) The conclusion is that the claim is unsound. c) The claim does not provide evidence for the truthfulness of the Ecologist s conclusion.

3 d) This is the correct answer because it describes the role that the claim plays in the Ecologist s argument. The Ecologist concludes that the claim is unsound. In other words, the whole argument is directed toward disproving the claim. e) That some maintain that...there will inevitably be a crisis, is stated as a fact and not an intermediate conclusion. The correct answer addresses the relationship of the claim to the Ecologist s conclusion. Furthermore, the Ecologist s evidence (that an unlikely assumption is required), functions to disprove the claim and is therefore in line with the correct answer. 5) Analyzing the Stimulus Here two fact patterns are presented. As the word nevertheless suggests, these two fact patterns point in differing directions. a) Even if this were true, the contagiousness of the disease is irrelevant since we have already established that there are fewer cases of the disease in Country X. In any case, it does not address why the mortality of disease P is so high b) This would not explain why the residents of Country X are more likely to die of the disease. c) This is the correct answer because it explains why the mortality for disease P is so high in Country X even though the incidence is low. If cases are only diagnosed when they are severe, by the time the diagnosis occurs it might already be too late for the patients. d) Even if this were true, it does not explain why the mortality from disease P is so high. e) Even if this were true, we are not concerned with other potentially fatal diseases. We want to explain why disease P has such a high mortality despite its low incidence. The correct answer does not refute either of the fact patterns and explains why despite the low incidence, the mortality for disease P is so high. 6) Analyzing the Stimulus The conclusion that the rehabilitation effort was not worthwhile is decisive. The evidence is certain and two pieces are presented: first, the only 18% of all otters that were found dead or alive, were successfully rehabilitated; second, there were many other otters that died and were never found (only 1/5 th were found in fact). This reasoning is implied and is informal: a program is worthless if it is only able to save 18% (or less) of affected otters. a) This answer does not challenge any of the evidence presented in the stimulus. If these other species of otters were not affected, it would not make a difference to the argument presented. b) A good case can be made for this answer. It addresses the second piece of evidence. However, we might be concerned that it does not pose an effective challenge (this

4 discrepancy could be easily explained), but unless we find a more powerful challenge, to the evidence, this answer should suffice. c) This does not address either of the two pieces of evidence offered in the passage. d) This does not address either of the two pieces of evidence offered in the passage. We are only concerned with otters. e) This answer brings up a problem with the conclusion (i.e. how do you define worthless ). However, we are looking for something that challenges the evidence presented and not the conclusion. The correct answer challenges one of the two pieces of evidence as we are asked to do by the stimulus. It does not challenge the conclusion nor the reasoning directly. 7) Analyzing the Stimulus The conclusion that cancer-patient support groups may have genuine therapeutic value is indecisive. The psychologist acknowledges this with the word may. The evidence is certain and two pieces are presented: first, that a weakened immune system increases vulnerability to cancer; second, participation in support groups reduces participant s stress levels. This reasoning is implied and is formal: - Given that a weakened a immune system increases vulnerability to cancer, we can conclude that a strong immune system decreases vulnerability to cancer; - Therefore, if participation in support groups decreases stress levels, the psychologist concludes that vulnerability to cancer will be decreased. - However, we can see that the psychologist has yet to draw a link between stress levels and vulnerability to cancer, though the facts do not preclude a link. One possibility is that stress levels are negatively related to immune system health. a) The functioning of cancer patients is not of concern here. We need to draw a link between stress levels and vulnerability to cancer. b) Even if disease were not a biochemical phenomenon, the psychologist is arguing that there is a link between stress levels and vulnerability to cancer and this answer does not address that claim. c) This is the correct answer because it draws a link between stress levels and vulnerability to cancer. It is stated in the first sentence that a weakened immune system increases vulnerability to cancer. If stress levels weaken the immune system, might therefore increase vulnerability to cancer (note that there might be a threshold effect). d) This is basically stated in the stimulus; however, it still fails to draw a required link between stress levels and vulnerability to cancer. e) While this answer seems to draw a link between stress and vulnerability to cancer through immune system health, it states that stress is an effect of weakened immune systems. For the link to be properly drawn, stress must be a cause of weakened immune systems.

5 Since the stem asks for a necessary assumption, we can check our answer using the negation and the fill in the blanks methods. This is the correct answer because it draws a link between stress levels and vulnerability to cancer, which is what required for the psychologist s argument to be properly drawn. 8) Analyzing the Stimulus The conclusion that adobe is an ideal material for building in desert environment is decisive. However, we should note that the it is an ideal material and not the ideal material. The evidence is certain and two pieces are presented: first, houses built of adobe are cool during the day and warm at night; second, other commonly used materials (note not all other building materials) do not have this effect. This reasoning is implied and is informal: the heating and cooling effect that adobe produces is ideal for desert environments. a) A good case can be made for this answer. However, when we go through the other answers, we see that E is a better answer. This is because the conclusion is that adobe is an ideal material and not an ideal substitute. b) While this is stated in the stimulus, we can see that it is a piece of evidence that points toward the conclusion and is not the conclusion itself. c) While this is strongly implied by the stimulus, we can see that it is a piece of evidence that points toward the conclusion and is not the conclusion itself. d) While this is stated in the stimulus, we can see that it is the reasoning that links the evidence to the conclusion and is not the conclusion itself. e) This is the correct answer because it correctly reiterates the conclusion of the argument. It can be differentiated from answer A. Only two answers describe the conclusion of the argument. E is a better answer than A because a does not describe the conclusion as well (there is no mention of adobe being a good substitute, though it may very well be). 9) Analyzing the Stimulus Here two differing fact patterns are presented. Two studies of the same area found two different results a) Though this might be true, it does not explain why the first study found that more plants of the same species had a patterned stems. b) Though this might be true, it does not explain why the first study found that more plants of the same species had a patterned stems. c) Though this might be true, it does not explain why the first study found that more plants of the same species had a patterned stems. This is because the results of the studies were presented as percentages of a total and not absolute numbers. d) This is correct answer because it explains why the first study found more patterning without refuting the second study. If the definition of patterning were loosened, more patterned stems would have been identified.

6 e) Though this might be true, it does not explain why the first study found that more plants of the same species had a patterned stems. The correct answer does not refute either of the fact patterns and explains why the two studies had different results 10) Analyzing the Stimulus The conclusion that the proposal would damage commercial fishing operations is decisive. The evidence is certain: over 20,000 people have signed a petition against the proposal. This reasoning is implied and is informal: a proposal that is opposed by a significant number of people will damage commercial fishing operations. It is important to note that the author of the letter acknowledges that this is only one indication. - Drawing a decisive conclusion using informal reasoning should raise eyebrows. Indeed, it is difficult to see how public opinion proves that the proposal will damage commercial fishing operations. This is likely a flaw question. a) The argument does not do this. In any case, it does not describe a flaw in the reasoning. b) Even if an alternative were proposed, this would not expose a flaw in the reasoning. c) Even if the author were disingenuous, this would not expose a flaw in the reasoning. d) A good case could be made for this answer. However, the answer would be better if it pointed out that opinion does not decisively prove the truthfulness of a statement. Since, there is no better answer, D is the correct answer. e) This answer is like B. It does not expose a flaw in the reasoning The correct answer is the only one that exposes a flaw in the reasoning which is implied. It shows that the whole argument is invalid. 11) Analyzing the Stimulus The conclusion that most universities offer a more in-depth and cosmopolitan education that ever before is decisive. It is important to note that it is most universities and that their offerings are better than ever before. The evidence is certain and is acknowledged to be one example: most history courses now have reading that mentions Africa, Asia and indigenous America after ancient periods, whereas in the past most did not. This reasoning is implied and is informal: courses that mention contemporary foreign history are cosmopolitan OR in-depth than those that do not. a) This answer neither strengthens the evidence presented nor the reasoning. What students find interesting is irrelevant to the conclusion that courses are more in-depth and cosmopolitan than ever before. b) This answer neither strengthens the evidence presented nor the reasoning. Innovative study abroad programs are irrelevant to the conclusion that courses are more in-depth and cosmopolitan than ever before.

7 c) This is the correct answer because it verifies the implied reasoning in the passage. d) While cultural inclusiveness pertains to cosmopolitanism, this answer would weaken the argument more than anything. In any case, even if this were true, it does not negate the fact that because some courses are more cosmopolitan, courses in general are now more cosmopolitan than they were previously. e) If this were true, it would attack the reasoning in the passage and severely weaken the conclusion, not strengthen it. The answer to a strengthen question must either verify the reasoning in the stimulus, support the evidence provided or add additional evidence in line with the reasoning and conclusion. The correct answer does just this. Some other answers actually weaken the argument. 12) Analyzing the Stimulus The conclusion that disclosure policies undermine the goal of informing the public is decisive. The evidence is uncertain: airlines will be less likely (not will, period) to give complete reports. This reasoning is explicit and is informal: airlines will be less likely to give complete reports and consumers will therefore obtain incorrect information. - The fact that a decisive conclusion is supported with uncertain evidence and informal reasoning should raise eyebrows. a) This is the correct answer because it addresses a flaw in the reasoning. Even if the reports were incomplete, this does not mean that they will be outright incorrect or that the public will not be more informed. b) We are not concerned with the public s right to information, but whether the public will be better informed. c) While this may be true, this answer does not address the author s argument that the act of airlines providing incomplete reports will cause the public to be less informed. d) The responsibility of airlines is of no material concern to the conclusion of the argument or the reasoning. e) The revenue of airlines is of no material concern to the conclusion of the argument or the reasoning. The correct answer is the only one that addresses the reasoning implied in the argument. It shows why the evidence does not fully support the conclusion and that the whole argument is invalid. 13) Analyzing the Stimulus The conclusion that economists overestimate the degree that money motivates people in their career choices is decisive. The evidence is certain: many surveys show that high salary is not named as a significant motivator. However, it is important to note that firstly surveys are based on a representative sample. Secondly, the stimulus states that many surveys, and not all, indicate this. This reasoning is explicit and is informal: the surveys show that the claim of these economists is

8 incorrect. - Again, the facts that a decisive conclusion is based on informal reasoning and evidence that is less certain than is stated, points to a flaw. a) This might actually strengthen the argument by explaining why money is not a significant motivator for career choices. b) While this answer seems to be correct (it ostensibly addresses the reasoning by providing), it is not as good as answer C. This is because the conclusion is that people are not strongly motivated by money to choose one job over another. Even if people would prefer to have a higher salary (as the answer states), this does not mean that they are willing to choose a different career just for a higher salary (which economists claim). c) This is the correct answer because it exposes a flaw in the reasoning by showing how the survey data might not support the conclusion. If salary (which the surveys measured) does not comprise the only source of financial benefits for employees, then the survey data must be false. d) Like A, this answer would provide some support for the conclusion. e) Because only some people are in question, this might not have any material effect on the overall result of the survey. In any case, if most people were aware of this, the conclusion in the stimulus would gain credence. Both a B and C address a potential flaw in the reasoning which would weaken the argument. However, C is a superior answer to B for the reasons listed above. 14) Analyzing the Stimulus Here two different conclusions are presented. Firstly, some parents that the new law will better engage students in the learning process. Secondly, some researchers have argued that the reasoning of these parents is questionable (that is, the link between individual attention and engagement). The parents conclusion is indecisive (the only argue ); the conclusion of the researchers is decisive (they conclude ). The evidence presented by the parents is uncertain: they only argue that individual attention will increase. The evidence of the researchers is certain: their study showed that grades did not change despite an increase in individual attention. The reasoning of the parents is explicit and informal: if individual attention increases, so will student engagement. The reasoning of the researchers is implied and informal: if the grades did not change even with greater individual attention, individual attention cannot result in better student engagement. - We must note here that the researchers have not yet drawn a link between student engagement and grades. a) Discussion the mechanics of the study does not allow the researchers to draw their conclusion properly based on their current reasoning.

9 b) Essentially this answer suggests that the data of the study might be incorrect. While it is essential to close of this possibility, a number of assumptions in turn would have to be drawn to require this answer to be correct. For one thing, it would have to be established that the unequal treatment would not result in a change to the average. In any case, the survey results have yet to be linked to student engagement, which is a more glaring problem. Therefore, answer D is superior. c) Reductions in class size are in no way related to the current reasoning of the researchers. d) This is the correct answer because it draws a necessary link that completes the researcher s reasoning. The researchers concluded that the parents were wrong in thinking that individual attention was positively correlated with engagement. Their study only showed that individual attention resulted in lower grades. Drawing a link between lower grades and engagement is required for the researchers conclusion to be drawn. e) Parental support for the law is in no way related to the current reasoning of the researchers. Without assuming D, the researchers conclusion cannot be drawn since low grades are not related intrinsically to low engagement. While Answer B brings up a relevant point, it requires additional assumptions and does not address the most glaring problem. The negation and fill in the blanks techniques can be used to double check the answer. 15) Analyzing the Stimulus Here two different conclusions are presented. Firstly, Camille concludes decisively that manufacturers of water saving faucets exaggerate the amount of money such faucets can save. Secondly, Rebecca concludes decisively that manufacturer s claims are not exaggerated. The evidence presented by Camille is certain: people using these faucets will often let the water run longer. Note that people will do this often and not most of the time. The evidence presented by Rebecca is certain: she has saved money on her water bills since installing the faucet. Camille s reasoning is implied and informal: if people using these faucets leave the taps on for longer, they will use more water, meaning that the manufacturers claims are exaggerated. Rebecca s reasoning is implied and informal: if she has saved money, the manufacturers claims are not exaggerated. - It is important to note that her decisive conclusion is supported solely by a single example. a) What is in question is the water saving capacity of the faucets, not the overall cost. b) This is the correct answer because it exposes a link that Rebecca fails to make in her reasoning. Even if her overall water bills were reduced, this does not mean that they were reduced to the extent that manufacturers claimed they would be c) The consistence of the claims is irrelevant to Rebecca s reasoning.

10 d) Whether Rebecca is satisfied or not is irrelevant to her reasoning which pertains the manufacturers claims and not her subjective standard. e) If manufacturers claims rested on installing a certain number of faucets (i.e. they claim that a household can save some amount of money, overall), a good case could be made for this answer. However, we must note that Rebecca s reasoning rests on the fact that she has only installed one such faucet. Therefore, this answer fails to expose a flaw in her reasoning. This question essentially asks us to identify an assumption that the Rebecca s reasoning depends on. The correct answer exposes a link that Rebecca failed to draw between her evidence and her conclusion. In other words, the negation technique and the fill in the blanks technique can be used to double check the answer. 16) Analyzing the Stimulus The conclusion that disposing of old automobiles will reduce air pollution more than redesigning the plants is decisive. The evidence is certain: the plants account for just four percent of local air pollution, while automobile emissions account for a much greater amount. This reasoning is implied and is informal: since old cars contribute more to air pollution, buying and disposing of them must have a greater effect on air pollution. a) This is irrelevant given that these automobiles contribute 30% to air pollution regardless. b) Whether the company will save money or not is irrelevant to reasoning or the evidence in the argument. c) This is the correct answer because if it were true, it would weaken the reasoning that simply disposing of old cars will lead to a reduction in air pollution. If the cars recycled by the company are not contributing to air pollution, their removal will not reduce air pollution. d) This is irrelevant since we do not know how many automobiles made after 1980 exist relative to older cars. If it could be shown that new automobiles are worse for the environment than old automobiles, this would show that the company s strategy is not as efficient. However, it would still challenge the argument that disposing of cars will do more for reducing air pollution that will redesigning the factory. e) A reduction in citizen s complaints does not mean that pollution has been reduced to a greater extent. The correct answer is the only one which, if true precludes the conclusion (that disposing of old cars will do more for reducing air pollution that will redesigning the factory) from being properly drawn from the evidence. 17) Analyzing the Stimulus The conclusion that our ancestors were at least partially altruistic is decisive. It is important to note that this conclusions is very limited: the altruism is at least partial.

11 The evidence is certain: our ancestors were motivated by the desire to sacrifice themselves when doing so would ensure the survival of their children or close relatives. This reasoning is explicit and is formal: the sacrifice equated to a form of altruism therefore the ancestors were altruistic a) This is the correct answer since it parallels the argument in the stimulus better than all others. We note firstly that the conclusion ( some students manage their time well ) is limited, as is the conclusion in the stimulus; however, this is only a clue and does not get to the real issue, which is similarity in reasoning. We also see that the evidence is certain as is the conclusion. As well, the evidence presented is based on an if statement just as in the stimulus. Further the reasoning followed in the stimulus is that the topic of the evidence presented (an increase in studying time) is then equated with the object of the conclusion (good time management). b) The evidence presented is based on an if statement just as in the stimulus. However, we are missing a limited conclusion that the stimulus contains. More importantly, the topic of the evidence presented (not consuming other organisms) is nowhere equated with the object of the conclusion (photosynthesis). c) The reasoning in this answer is flawed because it is tautological. The reasoning in the stimulus does not contain such a blatant flaw. d) There is no equating of the objects of evidence and conclusion. The evidence is not established using an if statement. The conclusion is not limited. e) While the evidence is established using an if statement, the object of the evidence (being well designed) is not equated to the object of the conclusion (harmony with surroundings). Finally, the conclusion is not limited. The correct answer has reasoning which parallels the reasoning in the stimulus (an equating formula described above). The limited nature of the conclusion and the fact that the evidence is established using an if statment gives clues to the correct answer (since only answer A contains it). However, these are only clues and are not enough to establish the correct answer. 18) Analyzing the Stimulus The conclusion that the bus company should not have reprimanded the driver is indecisive. The evidence is certain and two pieces are presented: first, the accident would not have occurred if the garbage truck was traveling within the speed limit; second, the bus driver was abiding by all traffic regulations. This reasoning is implied and is informal: someone who follows a) all traffic regulations should not reprimanded when b) the accident would not occur had another party been driving at an excessive speed of another party, even if c) the collision could be avoided with faster reactions. a) This answer contains good points. However, the conclusion of the argument is that bus driver should not have been reprimanded and does address who is responsible for the accident.

12 b) This would be a good answer if the police report did confirm that the collision was completely the fault of the driver of the garbage truck. However, the police report only confirmed that the bus driver was abiding by all traffic regulations. c) The argument considers when a bus company should not reprimand a driver, not when it should. In any case, the driver of the bus did not violate any traffic regulations. d) A very good case could be made for this answer. However, the bus driver never made the claim that he could not have reasonably been expected to avoid the collision. He only claims that he could have if he had reacted faster. e) This is the correct answer. While many of the other answers support part of the reasoning, we see that this answer is the only one which firstly addresses the conclusion (that the driver should not have been reprimanded). More importantly we see that if this principle was true, it would support the driver s conclusion even though the principle does not contain all the elements of the driver s reasoning: the driver did not violate any regulations and therefore should not have been reprimanded. The correct answer is a principle which allows the driver s conclusion to be drawn based on the evidence which was presented. 19) This question was removed from scoring 20) Analyzing the Stimulus The conclusion that today s generation of television viewers exercise their imaginations less frequently is decisive. The evidence is certain and two piece are presented: first, radio drama required listeners to picture dramatic elements for themselves; second, radio drama has been replaced by television. This reasoning is explicit and is informal: because radio drama required listeners to use their imaginations and nowadays, people watch television and do not listen to radio dramas, people today use their imaginations less frequently. - Note that the historian has yet to make the claim that television watchers do not use their imaginations. The historian has led us to assume this based on common sense. a) The logic in this answer proceeds like this: if a one hour of television exercises ten units of imagination, and one hour of radio exercises twenty units, if the same amount of television was watched as radio was listened to, then there would be a net decrease in imagination exercised. As a result, the historian must have this assumption! However, this assumption is not required for a number of reasons. For one thing, even half an hour of television was watched for every hour of radio listened to, the net effect on imagination would still be negative. Therefore, the ratio does not have to be equivalent as the answer states. b) This assumption is not required for the argument to succeed and could actually weaken the argument. If radio was more popular and familiar before and television is more popular and familiar now, then the argument would not stand.

13 c) We are not concerned with the desireability of television, nor are we concerned with its ability to inhibit the development of creativity. We are concerned with exercising imagination. d) This is the correct answer because it addresses a gap a what if- in the reasoning. If people today are able to exercise their imaginations through other means apart from television (which as the historian implies, requires less imagination), then the total amount of imagination exercised may not necessarily have decreased. e) A very good case could be made for this answer. However, we are concerned not about viewers thinking about what they see, but rather exercising their imaginations. Therefore, this answer is flawed and is inferior to D. The correct answer is an assumption on which the reasoning depends: the conclusion was unable to cover every scenario and the answer covers this hypothetical. The what-if and negation technique would help us to double check this answer. 21) Analyzing the Stimulus The conclusion that most of the candidates have the necessary skills to be a good mayor is decisive. We can also note its scope: most candidates have the right skills. The evidence is certain and three pieces are presented: first, every candidate is a small business owner; second, most small business owners are competent managers; third, no competent manager lacks the skill to be a good mayor. This reasoning is explicit and is formal: Since it is formal logic, we can easily spot a flaw. Most small business owners are competent managers and therefore have the right skills. This does not mean that all small business owners who are candidates are competent. a) The reasoning here is flawed because in the second piece of evidence, sales department mentioned and not sales department at least a year. This is a different flaw than the one found in the stimulus. b) This is the correct answer because the reasoning in the answer has the same flaw as does the stimulus. The second piece of evidence most fat free foods are sugar free is too wide in scope, just as in the stimulus. Even if most fat free foods were sugar free, that does not mean most of the fat free foods on the menu are sugar free. c) The conclusion states never read any whereas the stimulus refers to a majority. d) The reasoning here is flawed because the conclusion refers to, most of the films and not most the avant garde films. This is a different flaw than the one found in the stimulus. e) The conclusion here can be properly drawn from the evidence. The correct answer has the same flaw in its reasoning as does argument in the stimulus. 22) Analyzing the Stimulus The conclusion that the invention of money occurred independently in more than one society is Indecisive: it seems probable The evidence is certain and two pieces are presented: first, the universality of money is matched

14 only by language; second, money is an artificial human invention whereas language is rooted in innate ability. This reasoning is implied and is informal: Since money is a universal convention and must be Invented, it must have been invented independently in different societies. - Here we see that there is a what if gap in the reasoning. The author has assumed that independent invention is even possible. a) This is the correct answer because it addresses one element of the conclusion which the author has taken for granted. If no societies were separated from others societies in such a way that they could evolve independently of each other, then money could not have been invented independently by more than one society. b) The independent invention of money does not depend on the independent development of language. c) The stimulus already has established that money is universal and an invention. d) The stimulus already has established that money is universal, whether it is useful or not has no bearing. e) The conclusion relates to independent development, not to the continuing use of money in all societies. The correct answer targets an element of the conclusion: the possibility of independent development. We can test it using the negation technique and what if techniques (if independence was impossible, could the answer be properly drawn?). 23) Analyzing the Stimulus The conclusion that strong laws against libel can make it impossible for anyone in the public eye to have a good reputation is decisive. The evidence is certain: no one will say anything bad about public figures with strong libel laws. This reasoning is implied and is formal: - Somehow the fact that no one will say anything bad about public figures will lead to it being impossible to have a good reputation. a) This is not necessary for the conclusion to be drawn. b) We are concerned with good reputations. This answer still fails to draw a necessary link between the lack of bad reputations and the lack of good reputations. c) We are not concerned with a precise definition of libel; we need to draw a link between good reputations and libel. d) The stimulus has already stated that strong libel laws will prevent any bad things being said about any public figures (whether these things have any basis or not). e) This is the correct answer because draws a link between the evidence and the conclusion. If libel laws make it impossible for anyone to have a bad reputation and it is necessary for at least some to have a bad reputation in order for anyone to have a good reputation, libel laws will (as the stimulus concludes) make having a good reputation impossible.

15 Since the stem asks for a necessary assumption, we can check our answer using the negation and the fill-in-the-blanks methods. This is the correct answer because it draws a link between the evidence (not being able to say anything bad about public figures) and the conclusion (it being impossible for public figures to have a good reputation). 24) Analyzing the Stimulus This stimulus contains only background information which cannot be questioned. a) While this may be true, nowhere in the stimulus is it stated that mammals benefit or do not benefit from eating cellulose (though we know that digestion of cellulose, which mammals cannot do, provides glucose). b) Just because extracts of beta-glucans in mushrooms have anti-tumour properties, does not mean mushrooms produce other substances which also have anti-tumour properties. c) This is the correct answer because it is fully supported by the facts in the stimulus. It is stated that as branching increases, so do anti-tumour properties. It is also stated that anti-tumour properties operate by increasing immune cell activity. d) There is no evidence for this. In fact it is only said that increasing immune cell activity is not a DIRECT way of killing cancer cells. This does not mean that immune cells do not kill cancer cells. e) While this is true for SOME mushrooms, there is no evidence that this is true for all other organisms. The correct answer is a new fact which must be true according to the facts in the stimulus. All of the other answers require facts that are never mentioned in the stimulus. 25) Analyzing the Stimulus The conclusion that laws are primarily successful because the behaviour prescribed has become custom is indecisive. Unless it is well defined (and here it isn t), the conclusion is difficult to refute (particularly when an abstract and unmeasureable concept like the reasons for the success of a law is under discussion). The evidence is uncertain: an example (manners) is described in general terms and the effect of laws is compared to it. This reasoning is implied and is informal: Laws and manners are similar phenomena to the extent that whatever applies to manners must also be true of laws. a) Nothing is said about the variation of laws or manners across society. b) Nothing is said for the reasons to adopt a law. c) This is the correct answer because it describes the comparison being made correctly. We know that manners are observed because contrary behaviour becomes unthinkable. The stimulus claims that in the same way laws compel people to act because to act otherwise would be uncustomary d) There is no evidence for this in the stimulus.

16 e) There is no evidence for this in the stimulus. The correct answer shows how the evidence points to the conclusion (the reason for compliance with laws is custom)